There's modest evidence to this effect (see below). Plus, there's a fair amount of evidence indicating its usefulness some neurological disorders, such as Amyotrophic Lateral Sclerosis (Lou Gehrig's disease)
Oral creatine monohydrate supplementation improves brain performance: a double-blind, placebo-controlled, cross-over trial.
Rae C, Digney AL, McEwan SR, Bates TC.
Discipline of Biochemistry, School of Molecular and Microbial Biosciences G08, The University of Sydney, Sydney, NSW 2006, Australia.
c.rae@mmb.usyd.edu.au
Creatine supplementation is in widespread use to enhance sports-fitness performance, and has been trialled successfully in the treatment of neurological, neuromuscular and atherosclerotic disease. Creatine plays a pivotal role in brain energy homeostasis, being a temporal and spatial buffer for cytosolic and mitochondrial pools of the cellular energy currency, adenosine triphosphate and its regulator, adenosine diphosphate. In this work, we tested the hypothesis that oral creatine supplementation (5 g d(-1) for six weeks) would enhance intelligence test scores and working memory performance in 45 young adult, vegetarian subjects in a double-blind, placebo-controlled, cross-over design. Creatine supplementation had a significant positive effect (p < 0.0001) on both working memory (backward digit span) and intelligence (Raven's Advanced Progressive Matrices), both tasks that require speed of processing. These findings underline a dynamic and significant role of brain energy capacity in influencing brain performance.
